<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>数据类型</title>
</head>
<body>
<script>
  var a = 1;
  var b = 1.1;
  var c = null;
  console.log(typeof a);
  console.log(typeof b);
  console.log(typeof c);//object类型
</script>
</body>
</html>